He is the man literary Ireland fears most. Stephen Joyce, the highly litigious grandson of Ireland's greatest writer, James Joyce, has devoted his life to fiercely protecting his grandfather's copyright, setting his lawyers on those foolhardy enough to take the Joyce name in vain or to reproduce Joyce's words without consent.

Few are spared. He has targeted publishing houses, internet readings and even an Irish composer who requested permission to quote 18 words of Finnegans Wake and received a letter saying: "To put it politely, my wife and I don't like your music."

But now, fearful for this month's mammoth celebrations of Joyce's masterpiece, Ulysses, Irish MPs yesterday rushed through emergency legislation which will prevent Mr Joyce from suing the government and the National Library over an exhibition which displays 500 pages of Joyce manuscripts bought for €12.6m in 2002.

"James Joyce and Ulysses" is the centrepiece of the Rejoyce festival commemorating the centenary of Bloomsday, the day on which Ulysses was set.

Stephen Joyce had warned the government and the library he would take any copyright infringement seriously.

Mr Joyce, now in his 70s, is the writer's only living descendant. He lives in France and has made considerable sums from suing over copyright infringement and from fees for rights.

The government said it was closing a copyright loophole.